Conventionally, various means to optically reproduce video or audio signals on video discs or compact discs have already been proposed, but such discs are unable to optically record a large quantity of information because of the limited recording space, even though they can record various information in a high density (10.sup.8 bits/cm.sub.2). The recording density of magnetic tapes for use in video cassette recorder is too low (one hundredth to that of laser discs) to record a large quantity of information.